Error importing plugin "classes.contrib.mypy.classes_plugin" cannot import name 'union_items' from 'mypy.types'

首先重现 issue 中的 Python 3.11 import，并检查 classes/contrib/mypy/typeops/call_signatures.py，traceback 在此显示了失败的 mypy.types import。检查已安装的 mypy 兼容性，并验证 import classes.contrib.mypy.classes_plugin 能够无错误完成。

Bug report

What's wrong

I am hitting the error on a clean installation with python3.11 on MacOS.

Python 3.11.1 (main, Dec 12 2022, 14:17:59) [Clang 14.0.0 (clang-1400.0.29.202)] on darwin
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>>> import classes.contrib.mypy.classes_plugin
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/uname/PycharmProjects/sandbox/.venv/lib/python3.11/site-packages/classes/contrib/mypy/classes_plugin.py", line 33, in <module>
    from classes.contrib.mypy.features import associated_type, supports, typeclass
  File "/Users/uname/PycharmProjects/sandbox/.venv/lib/python3.11/site-packages/classes/contrib/mypy/features/typeclass.py", line 17, in <module>
    from classes.contrib.mypy.typeops import (
  File "/Users/uname/PycharmProjects/sandbox/.venv/lib/python3.11/site-packages/classes/contrib/mypy/typeops/call_signatures.py", line 9, in <module>
    from mypy.types import TypeVarType, union_items
ImportError: cannot import name 'union_items' from 'mypy.types' (/Users/uname/PycharmProjects/sandbox/.venv/lib/python3.11/site-packages/mypy/types.cpython-311-darwin.so)

How is that should be

No errors

System information

• python version:
• classes version:
• mypy version: